The following discussion of the background to the invention is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge of the person skilled in the art in any jurisdiction as at the priority date of the invention.
Under normal conditions, the thyroid gland produces certain predetermined amounts of thyroid hormones as thyroxin (hereinafter referred to as [T4]), and tri-iodothyronine (hereinafter referred to as [FT3]) for proper regulation of body functions. In physiology, the main thyroid component to be regulated is the free form of [T4] called free thyroxin (hereinafter referred to as [FT4]). This regulation mechanism is known to operate according to a negative feedback process. The level of [FT4] is closely monitored by the hypothalamus pituitary (hereinafter referred to as HP) unit.
Hypothyroidism and hyperthyroidism are caused by an impaired function of the thyroid gland and manifest as an imbalance in the production of thyroid hormones. It afflicts a range of mammals including, but not limited to humans. Hence the term ‘patient(s)’ or ‘individual(s)’ afflicted by thyroid disease resulting in thyroid hormonal imbalance may refer to any mammal that is affected. Hypothyroidism results from under-activity of the thyroid with a decrease in production of thyroid hormones and hyperthyroidism results from over-activity of the thyroid with an increase in production of thyroid hormones. It is known that the HP compares the level of the [FT4] in the blood stream with a predetermined level or set point. The HP may stimulate the thyroid to produce more or less [FT4] by means of the thyroid stimulating hormone, the hormone hereinafter referred to as [TSH]. To illustrate, if the level of [FT4] exceeds the set point level, the stimulation of [TSH] will be reduced. When the detected level of [FT4] is below the set point level, the amount of [TSH] will be increased to keep the level of [FT4] as close as possible to the set point value. This negative feedback regulation mechanism is characterized by the relationship between [FT4] and [TSH].
There has been ongoing research on the relationship between [FT4] and [TSH]. Nevertheless, most current research assumes the physiological homeostatic operating set point as a relatively constant value which does not vary much across individuals.
Despite existing research on set point and the HPT system, there are currently no well-defined standards or methods for accurately defining or predicting the physiological homeostatic operating set point of a given individual, in particular the optimal set point correlating the optimal [TSH] and [FT4] levels for different individuals. There also exists a need to fine-tune the mathematical models to account for variation between the physiological homeostatic operating set point of different individuals, the result of the same which may be used for clinical applications.
The present invention seeks to provide a system and method that meet the above needs at least in part.